Novel Blade Design and Scaled Wake Methodologies Towards the Next-Generation of Offshore Wind Turbines

Open Access
- Author:
- Major, Desirae
- Graduate Program:
- Aerospace Engineering
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- October 24, 2024
- Committee Members:
- Amy Pritchett, Program Head/Chair
Mark Maughmer, Major Field Member
Mark Miller, Major Field Member
Sven Schmitz, Chair & Dissertation Advisor
Susan Stewart, Major Field Member
Kenneth Davis, Outside Unit & Field Member - Keywords:
- Wind Energy
LCOE
CFD
Wind Turbine Aerodynamics
Wind Turbine Design
Offshore Wind Turbines - Abstract:
- Trends in wind turbine design over the last several decades have seen a notable increase in rotor sizes to increase power production per turbine to meet the increasing global energy demand for carbon-neutral electricity sources. The technical challenges of increasing turbine size for offshore wind applications while keeping cost of energy low/competitive is a highly coupled problem: (i) larger rotor sizes mean increased cost for manufacture, transportation, and installation; and (ii) changes in blade loading for the highly flexible blades, especially when ocean/atmospheric interactions are considered, and impacts O&M cost. While some additive blade features and novel turbine controller strategies have been developed to address this coupled problem for pre-existing turbine designs, they are expensive, require time-consuming optimization, lead to new technical problems for fatigue loads, and introduce new modes of failure with added actuating mechanisms and electrical components. Given these challenges facing the design and development of future large-diameter offshore wind turbines, this work seeks to alleviate these up-scaling challenges in the preliminary design phase through the development of two novel wind turbine design methodologies: (i) a coupled fatigue, aerodynamics, and cost-scaled turbine (FACT) design objective function for an up-scaled rotor to identify the optimum design point for lowest cost of energy, and (ii) a model-scale rotor design procedure based on induced power to facilitate wind tunnel wake experimental testing of the novel mega-rotor designs of the future where notable geometric disparities exist. Results from this work demonstrate the novelty of the two design methodologies, both of which represent a notable shift in perspective for the goals of the rotor blade design and what parameters should be optimized/maximized. By beginning from first principles, the methodologies developed here are easily adaptable to current industrial rotor design practices for an up-scaled commercial rotor or comprehensive experimental wind tunnel wake studies to validate the benefits of these novel wind turbine designs towards the development of next-generation offshore wind turbines.